Pascal was your original example upthread, tho:
"Now, the other way around: you've got an embedded Scheme, but you hate all that parentheses and want to just code in Pascal. Fine. Write a little macro which will translate transparently your Pascal into Scheme. No runtime cost whatsoever and all the interop done for free. See the difference now?"
Yes, it was my example - exactly because there are multiple implementations of this very thing, this thread is littered with the links. My last remark was that the full, 100% standard-compliant Pascal, although impressive, is not very practical, and a lower level language is what is usually designed for this purpose.
OK, so I'm looking at https://github.com/soegaard/minipascal right now, and ok it looks like there's a couple thousand lines of racket code that will translate a very limited (no records, no reals, does not appear to be any pointers) pascal-like language.
So presumably for this to be exciting, it would have to be executing in a larger environment where it's surrounded by racket code doing its own thing. But now I don't see what's so special about that, and why that's different from, say, a python script that takes a string of fake-pascal, turns it into python thru an internal processor, and then calls an eval.
The value is in mixing semantic properties of multiple (dozens) of languages in your single environment. Building the first fundamental blocks may take time, for they are fundamental for a reason, but then adding new things on top is trivial.
So, this is essential for building rich DSLs. See my framework as an extreme example of such an approach.
